Make SkJpegCodec compatible with libjpeg

BUG=skia:4470
BUG=skia:4520
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1687863003

Review URL: https://codereview.chromium.org/1687863003
5 files changed